Obviously, they were designed by someone who has unlimited garage headroom
They don't look to be over 7' to the top when open, based of seeing a man standing next to them when open.
Most garage doors are at least 7 foot tall, and 8 foot & taller are becoming far more common.
and doesn't regularly find a foot of snow on top of his car...
Put the snow broom in the trunk, like most people. Open the trunk, clear off the snow so you're not an asshole to everyone behind you on the road, then get in.